By having just the shoulder supports on the seats makes a big difference in how far you stretch in the car when flipping or landing side to side. I don't care how tight the belts are, the body will move side to side if not properly supported.

If you think of your body as a lever and then you support the lever at the half way point(Ribs), but not at the top, then there is a natural tendency for your body to flex and stretch from the rib support up. If you then support the shoulder area, then your upper body cannot flex and stretch outward. Shoulder supports make a huge difference in how the body reacts in a crash.

The cowbell effect is one that I have heard guys complain about, but I've seen it fixed by both cutting it back(thinning the padding) and adding padding.

As far as comparing ones self to Steve Kinser; All I can say to that is that is like comparing Toy Poodles to Pit Bull's. The man is extremely strong and has the neck of a horse. There a very few people racing today that have his build and you cannot compare an 18 year old or anyone for that matter to Steve. What works for him cannot be the gauge that everyone judges themselves off of.